All the system/preconfigured reports will get created on startup if they aren't present.
So even if you managed to delete them somehow (not sure how that is possible) they should still be there after booting.

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That is exactly what happened. I was importing a report from the forums here that shows how much data was transferred per day. Further down in the thread there was an updated/corrected report so when I imported the corrected version, I mistakenly assumed that I needed to check that option.